In scientific communities images play a dominant role to convey a message but more important, as a tool for experimental output. The meaning of these images develops from annotation that is provided by the researchers. Annotation can be accomplished in a number of ways. In this paper we describe graphical and textual annotations that are developed from ontologies. The Internet has provided the research community a medium for exchange of images. Images are, however, not straightforwardly suitable for exchange. Knowledge about what is depicted in the image as well as specific image content is important for image understanding. This holds in particular for scientific images that are the result of experimentation. For the purpose of image exchange, that is query-based search, image retrieval mechanisms based on pixel content as well as semantics are developed. In the field of experimental imaging new paradigms will have to be developed so that a search query results in correct image collections.